CALCULUS BC WORKSHEET 1 ON VECTORS Work the following on notebook paper. Use your calculator on problems 10 and 13c only. 3 dy . 1. If x t 2 1 and y et , find dx 2. If a particle moves in the xy-plane so that at any time t > 0, its position vector is ln t 2 5t , 3t 2 , find its velocity vector at time t = 2. 3. A particle moves in the xy-plane so that at any time t, its coordinates are given by x t 5 1 and y 3t 4 2t 3 . Find its acceleration vector at t = 1. 4. If a particle moves in the xy-plane so that at time t its position vector is sin 3t vector at time t 2 , 3t , find the velocity 2 . 2 5. A particle moves on the curve y ln x so that its x-component has derivative x t t 1 for t 0. At time t = 0, the particle is at the point (1, 0). Find the position of the particle at time t = 1. 6. A particle moves in the xy-plane in such a way that its velocity vector is 1 t , t 3 . If the position vector at t = 0 is 5, 0 , find the position of the particle at t = 2. 7. A particle moves along the curve xy 10. If x 2 and dy 3, what is the value of dx ? dt dt 8. The position of a particle moving in the xy-plane is given by the parametric equations 3 x t 3 t 2 18t 5 and y t 3 6t 2 9t 4. For what value(s) of t is the particle at rest? 2 9. A curve C is defined by the parametric equations x t 3 and y t 2 5t 2. Write the equation of the line tangent to the graph of C at the point 8, 4 . 10. A particle moves in the xy-plane so that the position of the particle is given by x t 5t 3sin t and y t 8 t 1 cos t Find the velocity vector at the time when the particle’s horizontal position is x = 25. 11. The position of a particle at any time t 0 is given by x t t 2 3 and y t 2 3 t 3. (a) Find the magnitude of the velocity vector at time t = 5. (b) Find the total distance traveled by the particle from t = 0 to t = 5. 12. Point P x, y moves in the xy-plane in such a way that dx 1 (c) Find dy dx as a function of x. dy 2t for t 0. dt t 1 dt (a) Find the coordinates of P in terms of t given that t = 1, x ln 2 , and y = 0. (b) Write an equation expressing y in terms of x. (c) Find the average rate of change of y with respect to x as t varies from 0 to 4. (d) Find the instantaneous rate of change of y with respect to x when t = 1. and 13. Consider the curve C given by the parametric equations x 2 3cos t and y 3 2 sin t , for dy (b) Find the equation of the tangent line at the point where t 2 t . 4 (c) The curve C intersects the y-axis twice. Approximate the length of the curve between the two yintercepts. (a) Find dx as a function of t. 2 . Answers to Worksheet 1 on Vectors 3 dy 3t 2et 3tet 1. dx 2t 2 3 2. 9 , 12 14 3. 20, 24 5 5 5. , ln 2 2 6. 9, 4 7. 8. t = 3 9. y 4 11. (a) 2600 or 10 26 (b) 4. 3, 3 6 5 10. 7.008, 2.228 12. (a) ln t 1 , t 2 1 (c) 13. (a) 3 2 26 2 1 3 1 x 8 12 (c) t x 3 (b) y e x 1 1 or y e2 x 2e x . 2 16 ln 5 (d) 4 2 cot t 3 2 3 2 (b) y 3 2 x 2 3 2 (c) 3.756